# uncompyle6 version 3.2.3
# Python bytecode 3.6 (3379)
# Decompiled from: Python 3.6.8 |Anaconda custom (64-bit)| (default, Feb 21 2019, 18:30:04) [MSC v.1916 64 bit (AMD64)]
# Embedded file name: pydoc.py
"""Generate Python documentation in HTML or text for interactive use.

At the Python interactive prompt, calling help(thing) on a Python object
documents the object, and calling help() starts up an interactive
help session.

Or, at the shell command line outside of Python:

Run "pydoc <name>" to show documentation on something.  <name> may be
the name of a function, module, package, or a dotted reference to a
class or function within a module or module in a package.  If the
argument contains a path segment delimiter (e.g. slash on Unix,
backslash on Windows) it is treated as the path to a Python source file.

Run "pydoc -k <keyword>" to search for a keyword in the synopsis lines
of all available modules.

Run "pydoc -p <port>" to start an HTTP server on the given port on the
local machine.  Port number 0 can be used to get an arbitrary unused port.

Run "pydoc -b" to start an HTTP server on an arbitrary unused port and
open a Web browser to interactively browse documentation.  The -p option
can be used with the -b option to explicitly specify the server port.

Run "pydoc -w <name>" to write out the HTML documentation for a module
to a file named "<name>.html".

Module docs for core modules are assumed to be in

    https://docs.python.org/X.Y/library/

This can be overridden by setting the PYTHONDOCS environment variable
to a different URL or to a local directory containing the Library
Reference Manual pages.
"""
__all__ = ["help"]
__author__ = "Ka-Ping Yee <ping@lfw.org>"
__date__ = "26 February 2001"
__credits__ = "Guido van Rossum, for an excellent programming language.\nTommy Burnette, the original creator of manpy.\nPaul Prescod, for all his work on onlinehelp.\nRichard Chamberlain, for the first implementation of textdoc.\n"
import builtins, importlib._bootstrap, importlib._bootstrap_external, importlib.machinery, importlib.util, inspect, io, os, pkgutil, platform, re, sys, time, tokenize, urllib.parse, warnings
from collections import deque
from reprlib import Repr
from traceback import format_exception_only


def pathdirs():
    """Convert sys.path into a list of absolute, existing, unique paths."""
    dirs = []
    normdirs = []
    for dir in sys.path:
        dir = os.path.abspath(dir or ".")
        normdir = os.path.normcase(dir)
        if normdir not in normdirs:
            if os.path.isdir(dir):
                dirs.append(dir)
                normdirs.append(normdir)

    return dirs


def getdoc(object):
    """Get the doc string or comments for an object."""
    result = inspect.getdoc(object) or inspect.getcomments(object)
    return result and re.sub("^ *\n", "", result.rstrip()) or ""


def splitdoc(doc):
    """Split a doc string into a synopsis line (if any) and the rest."""
    lines = doc.strip().split("\n")
    if len(lines) == 1:
        return (lines[0], "")
    else:
        if len(lines) >= 2:
            if not lines[1].rstrip():
                return (lines[0], ("\n").join(lines[2:]))
        return ("", ("\n").join(lines))


def classname(object, modname):
    """Get a class name and qualify it with a module name if necessary."""
    name = object.__name__
    if object.__module__ != modname:
        name = object.__module__ + "." + name
    return name


def isdata(object):
    """Check if an object is of a type that probably means it's data."""
    return not (
        inspect.ismodule(object)
        or inspect.isclass(object)
        or inspect.isroutine(object)
        or inspect.isframe(object)
        or inspect.istraceback(object)
        or inspect.iscode(object)
    )


def replace(text, *pairs):
    """Do a series of global replacements on a string."""
    while pairs:
        text = pairs[1].join(text.split(pairs[0]))
        pairs = pairs[2:]

    return text


def cram(text, maxlen):
    """Omit part of a string if needed to make it fit in a maximum length."""
    if len(text) > maxlen:
        pre = max(0, (maxlen - 3) // 2)
        post = max(0, maxlen - 3 - pre)
        return text[:pre] + "..." + text[len(text) - post :]
    else:
        return text


_re_stripid = re.compile(" at 0x[0-9a-f]{6,16}(>+)$", re.IGNORECASE)


def stripid(text):
    """Remove the hexadecimal id from a Python object representation."""
    return _re_stripid.sub("\\1", text)


def _is_some_method(obj):
    return (
        inspect.isfunction(obj)
        or inspect.ismethod(obj)
        or inspect.isbuiltin(obj)
        or inspect.ismethoddescriptor(obj)
    )


def _is_bound_method(fn):
    """
    Returns True if fn is a bound method, regardless of whether
    fn was implemented in Python or in C.
    """
    if inspect.ismethod(fn):
        return True
    elif inspect.isbuiltin(fn):
        self = getattr(fn, "__self__", None)
        return not (inspect.ismodule(self) or self is None)
    else:
        return False


def allmethods(cl):
    methods = {}
    for key, value in inspect.getmembers(cl, _is_some_method):
        methods[key] = 1

    for base in cl.__bases__:
        methods.update(allmethods(base))

    for key in methods.keys():
        methods[key] = getattr(cl, key)

    return methods


def _split_list(s, predicate):
    """Split sequence s via predicate, and return pair ([true], [false]).
    
    The return value is a 2-tuple of lists,
        ([x for x in s if predicate(x)],
         [x for x in s if not predicate(x)])
    """
    yes = []
    no = []
    for x in s:
        if predicate(x):
            yes.append(x)
        else:
            no.append(x)

    return (yes, no)


def visiblename(name, all=None, obj=None):
    """Decide whether to show documentation on a variable."""
    if name in frozenset(
        {
            "__file__",
            "__version__",
            "__credits__",
            "__cached__",
            "__builtins__",
            "__date__",
            "__loader__",
            "__package__",
            "__spec__",
            "__author__",
            "__name__",
            "__path__",
            "__qualname__",
            "__doc__",
            "__slots__",
            "__module__",
        }
    ):
        return 0
    else:
        if name.startswith("__"):
            if name.endswith("__"):
                return 1
            if name.startswith("_"):
                if hasattr(obj, "_fields"):
                    return True
                if all is not None:
                    return name in all
        return not name.startswith("_")


def classify_class_attrs(object):
    """Wrap inspect.classify_class_attrs, with fixup for data descriptors."""
    results = []
    for name, kind, cls, value in inspect.classify_class_attrs(object):
        if inspect.isdatadescriptor(value):
            kind = "data descriptor"
        results.append((name, kind, cls, value))

    return results


def sort_attributes(attrs, object):
    """Sort the attrs list in-place by _fields and then alphabetically by name"""
    fields = getattr(object, "_fields", [])
    try:
        field_order = {name: i - len(fields) for i, name in enumerate(fields)}
    except TypeError:
        field_order = {}

    keyfunc = lambda attr: (field_order.get(attr[0], 0), attr[0])
    attrs.sort(key=keyfunc)


def ispackage(path):
    """Guess whether a path refers to a package directory."""
    if os.path.isdir(path):
        for ext in (".py", ".pyc"):
            if os.path.isfile(os.path.join(path, "__init__" + ext)):
                return True

    return False


def source_synopsis(file):
    line = file.readline()
    while line[:1] == "#" or not line.strip():
        line = file.readline()
        if not line:
            break

    line = line.strip()
    if line[:4] == 'r"""':
        line = line[1:]
    if line[:3] == '"""':
        line = line[3:]
        if line[-1:] == "\\":
            line = line[:-1]
        while not line.strip():
            line = file.readline()
            if not line:
                break

        result = line.split('"""')[0].strip()
    else:
        result = None
    return result


def synopsis(filename, cache={}):
    """Get the one-line summary out of a module file."""
    mtime = os.stat(filename).st_mtime
    lastupdate, result = cache.get(filename, (None, None))
    if lastupdate is None or lastupdate < mtime:
        if filename.endswith(tuple(importlib.machinery.BYTECODE_SUFFIXES)):
            loader_cls = importlib.machinery.SourcelessFileLoader
        else:
            if filename.endswith(tuple(importlib.machinery.EXTENSION_SUFFIXES)):
                loader_cls = importlib.machinery.ExtensionFileLoader
            else:
                loader_cls = None
            if loader_cls is None:
                try:
                    file = tokenize.open(filename)
                except OSError:
                    return

                with file:
                    result = source_synopsis(file)
            else:
                loader = loader_cls("__temp__", filename)
                spec = importlib.util.spec_from_file_location(
                    "__temp__", filename, loader=loader
                )
                try:
                    module = importlib._bootstrap._load(spec)
                except:
                    return

                del sys.modules["__temp__"]
                result = module.__doc__.splitlines()[0] if module.__doc__ else None
            cache[filename] = (mtime, result)
        return result


class ErrorDuringImport(Exception):
    """Errors that occurred while trying to import something to document it."""

    def __init__(self, filename, exc_info):
        self.filename = filename
        self.exc, self.value, self.tb = exc_info

    def __str__(self):
        exc = self.exc.__name__
        return "problem in %s - %s: %s" % (self.filename, exc, self.value)


def importfile(path):
    """Import a Python source file or compiled file given its path."""
    magic = importlib.util.MAGIC_NUMBER
    with open(path, "rb") as (file):
        is_bytecode = magic == file.read(len(magic))
    filename = os.path.basename(path)
    name, ext = os.path.splitext(filename)
    if is_bytecode:
        loader = importlib._bootstrap_external.SourcelessFileLoader(name, path)
    else:
        loader = importlib._bootstrap_external.SourceFileLoader(name, path)
    spec = importlib.util.spec_from_file_location(name, path, loader=loader)
    try:
        return importlib._bootstrap._load(spec)
    except:
        raise ErrorDuringImport(path, sys.exc_info())


def safeimport(path, forceload=0, cache={}):
    """Import a module; handle errors; return None if the module isn't found.
    
    If the module *is* found but an exception occurs, it's wrapped in an
    ErrorDuringImport exception and reraised.  Unlike __import__, if a
    package path is specified, the module at the end of the path is returned,
    not the package at the beginning.  If the optional 'forceload' argument
    is 1, we reload the module from disk (unless it's a dynamic extension)."""
    try:
        if forceload:
            if path in sys.modules:
                if path not in sys.builtin_module_names:
                    subs = [m for m in sys.modules if m.startswith(path + ".")]
                    for key in [path] + subs:
                        cache[key] = sys.modules[key]
                        del sys.modules[key]

        module = __import__(path)
    except:
        exc, value, tb = info = sys.exc_info()
        if path in sys.modules:
            raise ErrorDuringImport(sys.modules[path].__file__, info)
        else:
            if exc is SyntaxError:
                raise ErrorDuringImport(value.filename, info)
            else:
                if issubclass(exc, ImportError):
                    if value.name == path:
                        return
                    raise ErrorDuringImport(path, sys.exc_info())

    for part in path.split(".")[1:]:
        try:
            module = getattr(module, part)
        except AttributeError:
            return

    return module


class Doc:
    PYTHONDOCS = os.environ.get(
        "PYTHONDOCS", "https://docs.python.org/%d.%d/library" % sys.version_info[:2]
    )

    def document(self, object, name=None, *args):
        """Generate documentation for an object."""
        args = (object, name) + args
        if inspect.isgetsetdescriptor(object):
            return self.docdata(*args)
        else:
            if inspect.ismemberdescriptor(object):
                return self.docdata(*args)
                try:
                    if inspect.ismodule(object):
                        return self.docmodule(*args)
                    if inspect.isclass(object):
                        return self.docclass(*args)
                    if inspect.isroutine(object):
                        return self.docroutine(*args)
                except AttributeError:
                    pass

                if isinstance(object, property):
                    return self.docproperty(*args)
            return self.docother(*args)

    def fail(self, object, name=None, *args):
        """Raise an exception for unimplemented types."""
        message = "don't know how to document object%s of type %s" % (
            name and " " + repr(name),
            type(object).__name__,
        )
        raise TypeError(message)

    docmodule = docclass = docroutine = docother = docproperty = docdata = fail

    def getdocloc(
        self,
        object,
        basedir=os.path.join(
            sys.base_exec_prefix, "lib", "python%d.%d" % sys.version_info[:2]
        ),
    ):
        """Return the location of module docs or None"""
        try:
            file = inspect.getabsfile(object)
        except TypeError:
            file = "(built-in)"

        docloc = os.environ.get("PYTHONDOCS", self.PYTHONDOCS)
        basedir = os.path.normcase(basedir)
        if isinstance(object, type(os)):
            if (
                object.__name__
                in (
                    "errno",
                    "exceptions",
                    "gc",
                    "imp",
                    "marshal",
                    "posix",
                    "signal",
                    "sys",
                    "_thread",
                    "zipimport",
                )
                or file.startswith(basedir)
                and not file.startswith(os.path.join(basedir, "site-packages"))
            ):
                if object.__name__ not in ("xml.etree", "test.pydoc_mod"):
                    if docloc.startswith(("http://", "https://")):
                        docloc = "%s/%s" % (docloc.rstrip("/"), object.__name__.lower())
                    else:
                        docloc = os.path.join(docloc, object.__name__.lower() + ".html")
                docloc = None
            return docloc


class HTMLRepr(Repr):
    """Class for safely making an HTML representation of a Python object."""

    def __init__(self):
        Repr.__init__(self)
        self.maxlist = self.maxtuple = 20
        self.maxdict = 10
        self.maxstring = self.maxother = 100

    def escape(self, text):
        return replace(text, "&", "&amp;", "<", "&lt;", ">", "&gt;")

    def repr(self, object):
        return Repr.repr(self, object)

    def repr1(self, x, level):
        if hasattr(type(x), "__name__"):
            methodname = "repr_" + ("_").join(type(x).__name__.split())
            if hasattr(self, methodname):
                return getattr(self, methodname)(x, level)
            return self.escape(cram(stripid(repr(x)), self.maxother))

    def repr_string(self, x, level):
        test = cram(x, self.maxstring)
        testrepr = repr(test)
        if "\\" in test:
            if "\\" not in replace(testrepr, "\\\\", ""):
                return "r" + testrepr[0] + self.escape(test) + testrepr[0]
            return re.sub(
                "((\\\\[\\\\abfnrtv\\'\"]|\\\\[0-9]..|\\\\x..|\\\\u....)+)",
                '<font color="#c040c0">\\1</font>',
                self.escape(testrepr),
            )

    repr_str = repr_string

    def repr_instance(self, x, level):
        try:
            return self.escape(cram(stripid(repr(x)), self.maxstring))
        except:
            return self.escape("<%s instance>" % x.__class__.__name__)

    repr_unicode = repr_string


class HTMLDoc(Doc):
    """Formatter class for HTML documentation."""

    _repr_instance = HTMLRepr()
    repr = _repr_instance.repr
    escape = _repr_instance.escape

    def page(self, title, contents):
        """Format an HTML page."""
        return (
            '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">\n<html><head><title>Python: %s</title>\n<meta http-equiv="Content-Type" content="text/html; charset=utf-8">\n</head><body bgcolor="#f0f0f8">\n%s\n</body></html>'
            % (title, contents)
        )

    def heading(self, title, fgcol, bgcol, extras=""):
        """Format a page heading."""
        return (
            '\n<table width="100%%" cellspacing=0 cellpadding=2 border=0 summary="heading">\n<tr bgcolor="%s">\n<td valign=bottom>&nbsp;<br>\n<font color="%s" face="helvetica, arial">&nbsp;<br>%s</font></td\n><td align=right valign=bottom\n><font color="%s" face="helvetica, arial">%s</font></td></tr></table>\n    '
            % (bgcol, fgcol, title, fgcol, extras or "&nbsp;")
        )

    def section(
        self,
        title,
        fgcol,
        bgcol,
        contents,
        width=6,
        prelude="",
        marginalia=None,
        gap="&nbsp;",
    ):
        """Format a section with a heading."""
        if marginalia is None:
            marginalia = "<tt>" + "&nbsp;" * width + "</tt>"
        result = (
            '<p>\n<table width="100%%" cellspacing=0 cellpadding=2 border=0 summary="section">\n<tr bgcolor="%s">\n<td colspan=3 valign=bottom>&nbsp;<br>\n<font color="%s" face="helvetica, arial">%s</font></td></tr>\n    '
            % (bgcol, fgcol, title)
        )
        if prelude:
            result = (
                result
                + '\n<tr bgcolor="%s"><td rowspan=2>%s</td>\n<td colspan=2>%s</td></tr>\n<tr><td>%s</td>'
                % (bgcol, marginalia, prelude, gap)
            )
        else:
            result = result + '\n<tr><td bgcolor="%s">%s</td><td>%s</td>' % (
                bgcol,
                marginalia,
                gap,
            )
        return result + '\n<td width="100%%">%s</td></tr></table>' % contents

    def bigsection(self, title, *args):
        """Format a section with a big heading."""
        title = "<big><strong>%s</strong></big>" % title
        return self.section(title, *args)

    def preformat(self, text):
        """Format literal preformatted text."""
        text = self.escape(text.expandtabs())
        return replace(
            text, "\n\n", "\n \n", "\n\n", "\n \n", " ", "&nbsp;", "\n", "<br>\n"
        )

    def multicolumn(self, list, format, cols=4):
        """Format a list of items into a multi-column list."""
        result = ""
        rows = (len(list) + cols - 1) // cols
        for col in range(cols):
            result = result + '<td width="%d%%" valign=top>' % (100 // cols)
            for i in range(rows * col, rows * col + rows):
                if i < len(list):
                    result = result + format(list[i]) + "<br>\n"

            result = result + "</td>"

        return '<table width="100%%" summary="list"><tr>%s</tr></table>' % result

    def grey(self, text):
        return '<font color="#909090">%s</font>' % text

    def namelink(self, name, *dicts):
        """Make a link for an identifier, given name-to-URL mappings."""
        for dict in dicts:
            if name in dict:
                return '<a href="%s">%s</a>' % (dict[name], name)

        return name

    def classlink(self, object, modname):
        """Make a link for a class."""
        name, module = object.__name__, sys.modules.get(object.__module__)
        if hasattr(module, name):
            if getattr(module, name) is object:
                return '<a href="%s.html#%s">%s</a>' % (
                    module.__name__,
                    name,
                    classname(object, modname),
                )
            return classname(object, modname)

    def modulelink(self, object):
        """Make a link for a module."""
        return '<a href="%s.html">%s</a>' % (object.__name__, object.__name__)

    def modpkglink(self, modpkginfo):
        """Make a link for a module or package to display in an index."""
        name, path, ispackage, shadowed = modpkginfo
        if shadowed:
            return self.grey(name)
        else:
            if path:
                url = "%s.%s.html" % (path, name)
            else:
                url = "%s.html" % name
            if ispackage:
                text = "<strong>%s</strong>&nbsp;(package)" % name
            else:
                text = name
            return '<a href="%s">%s</a>' % (url, text)

    def filelink(self, url, path):
        """Make a link to source file."""
        return '<a href="file:%s">%s</a>' % (url, path)

    def markup(self, text, escape=None, funcs={}, classes={}, methods={}):
        """Mark up some plain text, given a context of symbols to look for.
        Each context dictionary maps object names to anchor names."""
        escape = escape or self.escape
        results = []
        here = 0
        pattern = re.compile(
            "\\b((http|ftp)://\\S+[\\w/]|RFC[- ]?(\\d+)|PEP[- ]?(\\d+)|(self\\.)?(\\w+))"
        )
        while True:
            match = pattern.search(text, here)
            if not match:
                break
            start, end = match.span()
            results.append(escape(text[here:start]))
            all, scheme, rfc, pep, selfdot, name = match.groups()
            if scheme:
                url = escape(all).replace('"', "&quot;")
                results.append('<a href="%s">%s</a>' % (url, url))
            else:
                if rfc:
                    url = "http://www.rfc-editor.org/rfc/rfc%d.txt" % int(rfc)
                    results.append('<a href="%s">%s</a>' % (url, escape(all)))
                else:
                    if pep:
                        url = "http://www.python.org/dev/peps/pep-%04d/" % int(pep)
                        results.append('<a href="%s">%s</a>' % (url, escape(all)))
                    else:
                        if selfdot:
                            if text[end : end + 1] == "(":
                                results.append("self." + self.namelink(name, methods))
                            else:
                                results.append("self.<strong>%s</strong>" % name)
                        else:
                            if text[end : end + 1] == "(":
                                results.append(
                                    self.namelink(name, methods, funcs, classes)
                                )
                            else:
                                results.append(self.namelink(name, classes))
            here = end

        results.append(escape(text[here:]))
        return ("").join(results)

    def formattree(self, tree, modname, parent=None):
        """Produce HTML for a class tree as given by inspect.getclasstree()."""
        result = ""
        for entry in tree:
            if type(entry) is type(()):
                c, bases = entry
                result = result + '<dt><font face="helvetica, arial">'
                result = result + self.classlink(c, modname)
                if bases:
                    if bases != (parent,):
                        parents = []
                        for base in bases:
                            parents.append(self.classlink(base, modname))

                        result = result + "(" + (", ").join(parents) + ")"
                result = result + "\n</font></dt>"
            elif type(entry) is type([]):
                result = result + "<dd>\n%s</dd>\n" % self.formattree(entry, modname, c)

        return "<dl>\n%s</dl>\n" % result

    def docmodule(self, object, name=None, mod=None, *ignored):
        """Produce HTML documentation for a module object."""
        name = object.__name__
        try:
            all = object.__all__
        except AttributeError:
            all = None

        parts = name.split(".")
        links = []
        for i in range(len(parts) - 1):
            links.append(
                '<a href="%s.html"><font color="#ffffff">%s</font></a>'
                % ((".").join(parts[: i + 1]), parts[i])
            )

        linkedname = (".").join(links + parts[-1:])
        head = "<big><big><strong>%s</strong></big></big>" % linkedname
        try:
            path = inspect.getabsfile(object)
            url = urllib.parse.quote(path)
            filelink = self.filelink(url, path)
        except TypeError:
            filelink = "(built-in)"

        info = []
        if hasattr(object, "__version__"):
            version = str(object.__version__)
            if version[:11] == "$Revision: ":
                if version[-1:] == "$":
                    version = version[11:-1].strip()
            info.append("version %s" % self.escape(version))
        if hasattr(object, "__date__"):
            info.append(self.escape(str(object.__date__)))
        if info:
            head = head + " (%s)" % (", ").join(info)
        docloc = self.getdocloc(object)
        if docloc is not None:
            docloc = '<br><a href="%(docloc)s">Module Reference</a>' % locals()
        else:
            docloc = ""
        result = self.heading(
            head, "#ffffff", "#7799ee", '<a href=".">index</a><br>' + filelink + docloc
        )
        modules = inspect.getmembers(object, inspect.ismodule)
        classes, cdict = [], {}
        for key, value in inspect.getmembers(object, inspect.isclass):
            if all is not None or (inspect.getmodule(value) or object) is object:
                if visiblename(key, all, object):
                    classes.append((key, value))
                    cdict[key] = cdict[value] = "#" + key

        for key, value in classes:
            for base in value.__bases__:
                key, modname = base.__name__, base.__module__
                module = sys.modules.get(modname)
                if modname != name:
                    cdict[key] = cdict[base] = (
                        module
                        and hasattr(module, key)
                        and getattr(module, key) is base
                        and key not in cdict
                        and modname + ".html#" + key
                    )

        funcs, fdict = [], {}
        for key, value in inspect.getmembers(object, inspect.isroutine):
            if (
                all is not None
                or inspect.isbuiltin(value)
                or inspect.getmodule(value) is object
            ):
                if visiblename(key, all, object):
                    funcs.append((key, value))
                    fdict[key] = "#-" + key
                    fdict[value] = inspect.isfunction(value) and fdict[key]

        data = []
        for key, value in inspect.getmembers(object, isdata):
            if visiblename(key, all, object):
                data.append((key, value))

        doc = self.markup(getdoc(object), self.preformat, fdict, cdict)
        doc = doc and "<tt>%s</tt>" % doc
        result = result + "<p>%s</p>\n" % doc
        if hasattr(object, "__path__"):
            modpkgs = []
            for importer, modname, ispkg in pkgutil.iter_modules(object.__path__):
                modpkgs.append((modname, name, ispkg, 0))

            modpkgs.sort()
            contents = self.multicolumn(modpkgs, self.modpkglink)
            result = result + self.bigsection(
                "Package Contents", "#ffffff", "#aa55cc", contents
            )
        else:
            if modules:
                contents = self.multicolumn(modules, lambda t: self.modulelink(t[1]))
                result = result + self.bigsection(
                    "Modules", "#ffffff", "#aa55cc", contents
                )
        if classes:
            classlist = [value for key, value in classes]
            contents = [self.formattree(inspect.getclasstree(classlist, 1), name)]
            for key, value in classes:
                contents.append(self.document(value, key, name, fdict, cdict))

            result = result + self.bigsection(
                "Classes", "#ffffff", "#ee77aa", (" ").join(contents)
            )
        if funcs:
            contents = []
            for key, value in funcs:
                contents.append(self.document(value, key, name, fdict, cdict))

            result = result + self.bigsection(
                "Functions", "#ffffff", "#eeaa77", (" ").join(contents)
            )
        if data:
            contents = []
            for key, value in data:
                contents.append(self.document(value, key))

            result = result + self.bigsection(
                "Data", "#ffffff", "#55aa55", ("<br>\n").join(contents)
            )
        if hasattr(object, "__author__"):
            contents = self.markup(str(object.__author__), self.preformat)
            result = result + self.bigsection("Author", "#ffffff", "#7799ee", contents)
        if hasattr(object, "__credits__"):
            contents = self.markup(str(object.__credits__), self.preformat)
            result = result + self.bigsection("Credits", "#ffffff", "#7799ee", contents)
        return result

    def docclass(self, object, name=None, mod=None, funcs={}, classes={}, *ignored):
        """Produce HTML documentation for a class object."""
        realname = object.__name__
        name = name or realname
        bases = object.__bases__
        contents = []
        push = contents.append

        class HorizontalRule:
            def __init__(self):
                self.needone = 0

            def maybe(self):
                if self.needone:
                    push("<hr>\n")
                self.needone = 1

        hr = HorizontalRule()
        mro = deque(inspect.getmro(object))
        if len(mro) > 2:
            hr.maybe()
            push("<dl><dt>Method resolution order:</dt>\n")
            for base in mro:
                push("<dd>%s</dd>\n" % self.classlink(base, object.__module__))

            push("</dl>\n")

        def spill(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    try:
                        value = getattr(object, name)
                    except Exception:
                        push(self._docdescriptor(name, value, mod))
                    else:
                        push(
                            self.document(
                                value, name, mod, funcs, classes, mdict, object
                            )
                        )

                    push("\n")

            return attrs

        def spilldescriptors(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    push(self._docdescriptor(name, value, mod))

            return attrs

        def spilldata(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    base = self.docother(getattr(object, name), name, mod)
                    if callable(value) or inspect.isdatadescriptor(value):
                        doc = getattr(value, "__doc__", None)
                    else:
                        doc = None
                    if doc is None:
                        push("<dl><dt>%s</dl>\n" % base)
                    else:
                        doc = self.markup(
                            getdoc(value), self.preformat, funcs, classes, mdict
                        )
                        doc = "<dd><tt>%s</tt>" % doc
                        push("<dl><dt>%s%s</dl>\n" % (base, doc))
                    push("\n")

            return attrs

        attrs = [
            (name, kind, cls, value)
            for name, kind, cls, value in classify_class_attrs(object)
            if visiblename(name, obj=object)
        ]
        mdict = {}
        for key, kind, homecls, value in attrs:
            mdict[key] = anchor = "#" + name + "-" + key
            try:
                value = getattr(object, name)
            except Exception:
                pass

            try:
                mdict[value] = anchor
            except TypeError:
                pass

        while attrs:
            if mro:
                thisclass = mro.popleft()
            else:
                thisclass = attrs[0][2]
            attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)
            if thisclass is builtins.object:
                attrs = inherited
                continue
            else:
                if thisclass is object:
                    tag = "defined here"
                else:
                    tag = "inherited from %s" % self.classlink(
                        thisclass, object.__module__
                    )
                tag += ":<br>\n"
                sort_attributes(attrs, object)
                attrs = spill("Methods %s" % tag, attrs, lambda t: t[1] == "method")
                attrs = spill(
                    "Class methods %s" % tag, attrs, lambda t: t[1] == "class method"
                )
                attrs = spill(
                    "Static methods %s" % tag, attrs, lambda t: t[1] == "static method"
                )
                attrs = spilldescriptors(
                    "Data descriptors %s" % tag,
                    attrs,
                    lambda t: t[1] == "data descriptor",
                )
                attrs = spilldata(
                    "Data and other attributes %s" % tag,
                    attrs,
                    lambda t: t[1] == "data",
                )
                if not attrs == []:
                    raise AssertionError
            attrs = inherited

        contents = ("").join(contents)
        if name == realname:
            title = '<a name="%s">class <strong>%s</strong></a>' % (name, realname)
        else:
            title = '<strong>%s</strong> = <a name="%s">class %s</a>' % (
                name,
                name,
                realname,
            )
        if bases:
            parents = []
            for base in bases:
                parents.append(self.classlink(base, object.__module__))

            title = title + "(%s)" % (", ").join(parents)
        doc = self.markup(getdoc(object), self.preformat, funcs, classes, mdict)
        doc = doc and "<tt>%s<br>&nbsp;</tt>" % doc
        return self.section(title, "#000000", "#ffc8d8", contents, 3, doc)

    def formatvalue(self, object):
        """Format an argument default value as text."""
        return self.grey("=" + self.repr(object))

    def docroutine(
        self, object, name=None, mod=None, funcs={}, classes={}, methods={}, cl=None
    ):
        """Produce HTML documentation for a function or method object."""
        realname = object.__name__
        name = name or realname
        anchor = (cl and cl.__name__ or "") + "-" + name
        note = ""
        skipdocs = 0
        if _is_bound_method(object):
            imclass = object.__self__.__class__
            if cl:
                pass
        if imclass is not cl:
            note = " from " + self.classlink(imclass, mod)
        else:
            if object.__self__ is not None:
                note = " method of %s instance" % self.classlink(
                    object.__self__.__class__, mod
                )
            else:
                note = " unbound %s method" % self.classlink(imclass, mod)
        if name == realname:
            title = '<a name="%s"><strong>%s</strong></a>' % (anchor, realname)
        else:
            if cl:
                if realname in cl.__dict__:
                    if cl.__dict__[realname] is object:
                        reallink = '<a href="#%s">%s</a>' % (
                            cl.__name__ + "-" + realname,
                            realname,
                        )
                        skipdocs = 1
                    reallink = realname
                title = '<a name="%s"><strong>%s</strong></a> = %s' % (
                    anchor,
                    name,
                    reallink,
                )
            argspec = None
            if inspect.isroutine(object):
                try:
                    signature = inspect.signature(object)
                except (ValueError, TypeError):
                    signature = None

                if signature:
                    argspec = str(signature)
                    if realname == "<lambda>":
                        title = "<strong>%s</strong> <em>lambda</em> " % name
                        argspec = argspec[1:-1]
            if not argspec:
                argspec = "(...)"
            decl = (
                title
                + self.escape(argspec)
                + (note and self.grey('<font face="helvetica, arial">%s</font>' % note))
            )
            if skipdocs:
                return "<dl><dt>%s</dt></dl>\n" % decl
            doc = self.markup(getdoc(object), self.preformat, funcs, classes, methods)
            doc = doc and "<dd><tt>%s</tt></dd>" % doc
            return "<dl><dt>%s</dt>%s</dl>\n" % (decl, doc)

    def _docdescriptor(self, name, value, mod):
        results = []
        push = results.append
        if name:
            push("<dl><dt><strong>%s</strong></dt>\n" % name)
        if value.__doc__ is not None:
            doc = self.markup(getdoc(value), self.preformat)
            push("<dd><tt>%s</tt></dd>\n" % doc)
        push("</dl>\n")
        return ("").join(results)

    def docproperty(self, object, name=None, mod=None, cl=None):
        """Produce html documentation for a property."""
        return self._docdescriptor(name, object, mod)

    def docother(self, object, name=None, mod=None, *ignored):
        """Produce HTML documentation for a data object."""
        lhs = name and "<strong>%s</strong> = " % name or ""
        return lhs + self.repr(object)

    def docdata(self, object, name=None, mod=None, cl=None):
        """Produce html documentation for a data descriptor."""
        return self._docdescriptor(name, object, mod)

    def index(self, dir, shadowed=None):
        """Generate an HTML index for a directory of modules."""
        modpkgs = []
        if shadowed is None:
            shadowed = {}
        for importer, name, ispkg in pkgutil.iter_modules([dir]):
            if any((55296 <= ord(ch) <= 57343 for ch in name)):
                continue
            modpkgs.append((name, "", ispkg, name in shadowed))
            shadowed[name] = 1

        modpkgs.sort()
        contents = self.multicolumn(modpkgs, self.modpkglink)
        return self.bigsection(dir, "#ffffff", "#ee77aa", contents)


class TextRepr(Repr):
    """Class for safely making a text representation of a Python object."""

    def __init__(self):
        Repr.__init__(self)
        self.maxlist = self.maxtuple = 20
        self.maxdict = 10
        self.maxstring = self.maxother = 100

    def repr1(self, x, level):
        if hasattr(type(x), "__name__"):
            methodname = "repr_" + ("_").join(type(x).__name__.split())
            if hasattr(self, methodname):
                return getattr(self, methodname)(x, level)
            return cram(stripid(repr(x)), self.maxother)

    def repr_string(self, x, level):
        test = cram(x, self.maxstring)
        testrepr = repr(test)
        if "\\" in test:
            if "\\" not in replace(testrepr, "\\\\", ""):
                return "r" + testrepr[0] + test + testrepr[0]
            return testrepr

    repr_str = repr_string

    def repr_instance(self, x, level):
        try:
            return cram(stripid(repr(x)), self.maxstring)
        except:
            return "<%s instance>" % x.__class__.__name__


class TextDoc(Doc):
    """Formatter class for text documentation."""

    _repr_instance = TextRepr()
    repr = _repr_instance.repr

    def bold(self, text):
        """Format a string in bold by overstriking."""
        return ("").join((ch + "\x08" + ch for ch in text))

    def indent(self, text, prefix="    "):
        """Indent text by prepending a given prefix to each line."""
        if not text:
            return ""
        else:
            lines = [prefix + line for line in text.split("\n")]
            if lines:
                lines[-1] = lines[-1].rstrip()
            return ("\n").join(lines)

    def section(self, title, contents):
        """Format a section with a given heading."""
        clean_contents = self.indent(contents).rstrip()
        return self.bold(title) + "\n" + clean_contents + "\n\n"

    def formattree(self, tree, modname, parent=None, prefix=""):
        """Render in text a class tree as returned by inspect.getclasstree()."""
        result = ""
        for entry in tree:
            if type(entry) is type(()):
                c, bases = entry
                result = result + prefix + classname(c, modname)
                if bases:
                    if bases != (parent,):
                        parents = (classname(c, modname) for c in bases)
                        result = result + "(%s)" % (", ").join(parents)
                result = result + "\n"
            elif type(entry) is type([]):
                result = result + self.formattree(entry, modname, c, prefix + "    ")

        return result

    def docmodule(self, object, name=None, mod=None):
        """Produce text documentation for a given module object."""
        name = object.__name__
        synop, desc = splitdoc(getdoc(object))
        result = self.section("NAME", name + (synop and " - " + synop))
        all = getattr(object, "__all__", None)
        docloc = self.getdocloc(object)
        if docloc is not None:
            result = result + self.section(
                "MODULE REFERENCE",
                docloc
                + "\n\nThe following documentation is automatically generated from the Python\nsource files.  It may be incomplete, incorrect or include features that\nare considered implementation detail and may vary between Python\nimplementations.  When in doubt, consult the module reference at the\nlocation listed above.\n",
            )
        if desc:
            result = result + self.section("DESCRIPTION", desc)
        classes = []
        for key, value in inspect.getmembers(object, inspect.isclass):
            if all is not None or (inspect.getmodule(value) or object) is object:
                if visiblename(key, all, object):
                    classes.append((key, value))

        funcs = []
        for key, value in inspect.getmembers(object, inspect.isroutine):
            if (
                all is not None
                or inspect.isbuiltin(value)
                or inspect.getmodule(value) is object
            ):
                if visiblename(key, all, object):
                    funcs.append((key, value))

        data = []
        for key, value in inspect.getmembers(object, isdata):
            if visiblename(key, all, object):
                data.append((key, value))

        modpkgs = []
        modpkgs_names = set()
        if hasattr(object, "__path__"):
            for importer, modname, ispkg in pkgutil.iter_modules(object.__path__):
                modpkgs_names.add(modname)
                if ispkg:
                    modpkgs.append(modname + " (package)")
                else:
                    modpkgs.append(modname)

            modpkgs.sort()
            result = result + self.section("PACKAGE CONTENTS", ("\n").join(modpkgs))
        submodules = []
        for key, value in inspect.getmembers(object, inspect.ismodule):
            if value.__name__.startswith(name + "."):
                if key not in modpkgs_names:
                    submodules.append(key)

        if submodules:
            submodules.sort()
            result = result + self.section("SUBMODULES", ("\n").join(submodules))
        if classes:
            classlist = [value for key, value in classes]
            contents = [self.formattree(inspect.getclasstree(classlist, 1), name)]
            for key, value in classes:
                contents.append(self.document(value, key, name))

            result = result + self.section("CLASSES", ("\n").join(contents))
        if funcs:
            contents = []
            for key, value in funcs:
                contents.append(self.document(value, key, name))

            result = result + self.section("FUNCTIONS", ("\n").join(contents))
        if data:
            contents = []
            for key, value in data:
                contents.append(self.docother(value, key, name, maxlen=70))

            result = result + self.section("DATA", ("\n").join(contents))
        if hasattr(object, "__version__"):
            version = str(object.__version__)
            if version[:11] == "$Revision: ":
                if version[-1:] == "$":
                    version = version[11:-1].strip()
            result = result + self.section("VERSION", version)
        if hasattr(object, "__date__"):
            result = result + self.section("DATE", str(object.__date__))
        if hasattr(object, "__author__"):
            result = result + self.section("AUTHOR", str(object.__author__))
        if hasattr(object, "__credits__"):
            result = result + self.section("CREDITS", str(object.__credits__))
        try:
            file = inspect.getabsfile(object)
        except TypeError:
            file = "(built-in)"

        result = result + self.section("FILE", file)
        return result

    def docclass(self, object, name=None, mod=None, *ignored):
        """Produce text documentation for a given class object."""
        realname = object.__name__
        name = name or realname
        bases = object.__bases__

        def makename(c, m=object.__module__):
            return classname(c, m)

        if name == realname:
            title = "class " + self.bold(realname)
        else:
            title = self.bold(name) + " = class " + realname
        if bases:
            parents = map(makename, bases)
            title = title + "(%s)" % (", ").join(parents)
        doc = getdoc(object)
        contents = doc and [doc + "\n"] or []
        push = contents.append
        mro = deque(inspect.getmro(object))
        if len(mro) > 2:
            push("Method resolution order:")
            for base in mro:
                push("    " + makename(base))

            push("")

        class HorizontalRule:
            def __init__(self):
                self.needone = 0

            def maybe(self):
                if self.needone:
                    push("-" * 70)
                self.needone = 1

        hr = HorizontalRule()

        def spill(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    try:
                        value = getattr(object, name)
                    except Exception:
                        push(self._docdescriptor(name, value, mod))

                    push(self.document(value, name, mod, object))

            return attrs

        def spilldescriptors(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    push(self._docdescriptor(name, value, mod))

            return attrs

        def spilldata(msg, attrs, predicate):
            ok, attrs = _split_list(attrs, predicate)
            if ok:
                hr.maybe()
                push(msg)
                for name, kind, homecls, value in ok:
                    if callable(value) or inspect.isdatadescriptor(value):
                        doc = getdoc(value)
                    else:
                        doc = None
                    try:
                        obj = getattr(object, name)
                    except AttributeError:
                        obj = homecls.__dict__[name]

                    push((self.docother(obj, name, mod, maxlen=70, doc=doc)) + "\n")

            return attrs

        attrs = [
            (name, kind, cls, value)
            for name, kind, cls, value in classify_class_attrs(object)
            if visiblename(name, obj=object)
        ]
        while attrs:
            if mro:
                thisclass = mro.popleft()
            else:
                thisclass = attrs[0][2]
            attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)
            if thisclass is builtins.object:
                attrs = inherited
                continue
            else:
                if thisclass is object:
                    tag = "defined here"
                else:
                    tag = "inherited from %s" % classname(thisclass, object.__module__)
                sort_attributes(attrs, object)
                attrs = spill("Methods %s:\n" % tag, attrs, lambda t: t[1] == "method")
                attrs = spill(
                    "Class methods %s:\n" % tag, attrs, lambda t: t[1] == "class method"
                )
                attrs = spill(
                    "Static methods %s:\n" % tag,
                    attrs,
                    lambda t: t[1] == "static method",
                )
                attrs = spilldescriptors(
                    "Data descriptors %s:\n" % tag,
                    attrs,
                    lambda t: t[1] == "data descriptor",
                )
                attrs = spilldata(
                    "Data and other attributes %s:\n" % tag,
                    attrs,
                    lambda t: t[1] == "data",
                )
                if not attrs == []:
                    raise AssertionError
            attrs = inherited

        contents = ("\n").join(contents)
        if not contents:
            return title + "\n"
        else:
            return title + "\n" + self.indent(contents.rstrip(), " |  ") + "\n"

    def formatvalue(self, object):
        """Format an argument default value as text."""
        return "=" + self.repr(object)

    def docroutine(self, object, name=None, mod=None, cl=None):
        """Produce text documentation for a function or method object."""
        realname = object.__name__
        name = name or realname
        note = ""
        skipdocs = 0
        if _is_bound_method(object):
            imclass = object.__self__.__class__
            if cl:
                if imclass is not cl:
                    note = " from " + classname(imclass, mod)
                else:
                    if object.__self__ is not None:
                        note = " method of %s instance" % classname(
                            object.__self__.__class__, mod
                        )
                    else:
                        note = " unbound %s method" % classname(imclass, mod)
                    if name == realname:
                        title = self.bold(realname)
                    else:
                        if cl:
                            if realname in cl.__dict__:
                                if cl.__dict__[realname] is object:
                                    skipdocs = 1
                        title = self.bold(name) + " = " + realname
                    argspec = None
                    if inspect.isroutine(object):
                        try:
                            signature = inspect.signature(object)
                        except (ValueError, TypeError):
                            signature = None

                        if signature:
                            argspec = str(signature)
                            if realname == "<lambda>":
                                title = self.bold(name) + " lambda "
                                argspec = argspec[1:-1]
                    if not argspec:
                        argspec = "(...)"
                    decl = title + argspec + note
                    if skipdocs:
                        return decl + "\n"
                    doc = getdoc(object) or ""
                    return decl + "\n" + (doc and self.indent(doc).rstrip() + "\n")

    def _docdescriptor(self, name, value, mod):
        results = []
        push = results.append
        if name:
            push(self.bold(name))
            push("\n")
        doc = getdoc(value) or ""
        if doc:
            push(self.indent(doc))
            push("\n")
        return ("").join(results)

    def docproperty(self, object, name=None, mod=None, cl=None):
        """Produce text documentation for a property."""
        return self._docdescriptor(name, object, mod)

    def docdata(self, object, name=None, mod=None, cl=None):
        """Produce text documentation for a data descriptor."""
        return self._docdescriptor(name, object, mod)

    def docother(self, object, name=None, mod=None, parent=None, maxlen=None, doc=None):
        """Produce text documentation for a data object."""
        repr = self.repr(object)
        if maxlen:
            line = (name and name + " = " or "") + repr
            chop = maxlen - len(line)
            if chop < 0:
                repr = repr[:chop] + "..."
        line = (name and self.bold(name) + " = " or "") + repr
        if doc is not None:
            line += "\n" + self.indent(str(doc))
        return line


class _PlainTextDoc(TextDoc):
    """Subclass of TextDoc which overrides string styling"""

    def bold(self, text):
        return text


def pager(text):
    """The first time this is called, determine what kind of pager to use."""
    global pager
    pager = getpager()
    pager(text)


def getpager():
    """Decide what method to use for paging through text."""
    if not hasattr(sys.stdin, "isatty"):
        return plainpager
    if not hasattr(sys.stdout, "isatty"):
        return plainpager
    if not sys.stdin.isatty() or not sys.stdout.isatty():
        return plainpager
    use_pager = os.environ.get("MANPAGER") or os.environ.get("PAGER")
    if use_pager:
        if sys.platform == "win32":
            return lambda text: tempfilepager(plain(text), use_pager)
        if os.environ.get("TERM") in ("dumb", "emacs"):
            return lambda text: pipepager(plain(text), use_pager)
        return lambda text: pipepager(text, use_pager)
    if os.environ.get("TERM") in ("dumb", "emacs"):
        return plainpager
    if sys.platform == "win32":
        return lambda text: tempfilepager(plain(text), "more <")
    if hasattr(os, "system"):
        if os.system("(less) 2>/dev/null") == 0:
            return lambda text: pipepager(text, "less")
        import tempfile

        fd, filename = tempfile.mkstemp()
        os.close(fd)
        try:
            if hasattr(os, "system"):
                if os.system('more "%s"' % filename) == 0:
                    return lambda text: pipepager(text, "more")
                return ttypager
        finally:
            os.unlink(filename)


def plain(text):
    """Remove boldface formatting from text."""
    return re.sub(".\x08", "", text)


def pipepager(text, cmd):
    """Page through text by feeding it to another program."""
    import subprocess

    proc = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE)
    try:
        with io.TextIOWrapper(proc.stdin, errors="backslashreplace") as (pipe):
            try:
                pipe.write(text)
            except KeyboardInterrupt:
                pass

    except OSError:
        pass

    while True:
        try:
            proc.wait()
            break
        except KeyboardInterrupt:
            pass


def tempfilepager(text, cmd):
    """Page through text by invoking a program on a temporary file."""
    import tempfile

    filename = tempfile.mktemp()
    with open(filename, "w", errors="backslashreplace") as (file):
        file.write(text)
    try:
        os.system(cmd + ' "' + filename + '"')
    finally:
        os.unlink(filename)


def _escape_stdout(text):
    encoding = getattr(sys.stdout, "encoding", None) or "utf-8"
    return text.encode(encoding, "backslashreplace").decode(encoding)


def ttypager(text):
    """Page through text on a text terminal."""
    lines = plain(_escape_stdout(text)).split("\n")
    try:
        import tty

        fd = sys.stdin.fileno()
        old = tty.tcgetattr(fd)
        tty.setcbreak(fd)
        getchar = lambda: sys.stdin.read(1)
    except (ImportError, AttributeError, io.UnsupportedOperation):
        tty = None
        getchar = lambda: sys.stdin.readline()[:-1][:1]

    try:
        try:
            h = int(os.environ.get("LINES", 0))
        except ValueError:
            h = 0

        if h <= 1:
            h = 25
        r = inc = h - 1
        sys.stdout.write(("\n").join(lines[:inc]) + "\n")
        while lines[r:]:
            sys.stdout.write("-- more --")
            sys.stdout.flush()
            c = getchar()
            if c in ("q", "Q"):
                sys.stdout.write("\r          \r")
                break
            else:
                if c in ("\r", "\n"):
                    sys.stdout.write("\r          \r" + lines[r] + "\n")
                    r = r + 1
                    continue
                if c in ("b", "B", "\x1b"):
                    r = r - inc - inc
                    if r < 0:
                        r = 0
                sys.stdout.write("\n" + ("\n").join(lines[r : r + inc]) + "\n")
            r = r + inc

    finally:
        if tty:
            tty.tcsetattr(fd, tty.TCSAFLUSH, old)


def plainpager(text):
    """Simply print unformatted text.  This is the ultimate fallback."""
    sys.stdout.write(plain(_escape_stdout(text)))


def describe(thing):
    """Produce a short description of the given thing."""
    if inspect.ismodule(thing):
        if thing.__name__ in sys.builtin_module_names:
            return "built-in module " + thing.__name__
        if hasattr(thing, "__path__"):
            return "package " + thing.__name__
        return "module " + thing.__name__
    elif inspect.isbuiltin(thing):
        return "built-in function " + thing.__name__
    elif inspect.isgetsetdescriptor(thing):
        return "getset descriptor %s.%s.%s" % (
            thing.__objclass__.__module__,
            thing.__objclass__.__name__,
            thing.__name__,
        )
    elif inspect.ismemberdescriptor(thing):
        return "member descriptor %s.%s.%s" % (
            thing.__objclass__.__module__,
            thing.__objclass__.__name__,
            thing.__name__,
        )
    elif inspect.isclass(thing):
        return "class " + thing.__name__
    elif inspect.isfunction(thing):
        return "function " + thing.__name__
    elif inspect.ismethod(thing):
        return "method " + thing.__name__
    else:
        return type(thing).__name__


def locate(path, forceload=0):
    """Locate an object by name or dotted path, importing as necessary."""
    parts = [part for part in path.split(".") if part]
    module, n = (None, 0)
    while n < len(parts):
        nextmodule = safeimport((".").join(parts[: n + 1]), forceload)
        if nextmodule:
            module, n = nextmodule, n + 1
        else:
            break

    if module:
        object = module
    else:
        object = builtins
    for part in parts[n:]:
        try:
            object = getattr(object, part)
        except AttributeError:
            return

    return object


text = TextDoc()
plaintext = _PlainTextDoc()
html = HTMLDoc()


def resolve(thing, forceload=0):
    """Given an object or a path to an object, get the object and its name."""
    if isinstance(thing, str):
        object = locate(thing, forceload)
        if object is None:
            raise ImportError(
                "No Python documentation found for %r.\nUse help() to get the interactive help utility.\nUse help(str) for help on the str class."
                % thing
            )
        return (object, thing)
    else:
        name = getattr(thing, "__name__", None)
        return (thing, name if isinstance(name, str) else None)


def render_doc(
    thing, title="Python Library Documentation: %s", forceload=0, renderer=None
):
    """Render text documentation, given an object or a path to an object."""
    if renderer is None:
        renderer = text
    object, name = resolve(thing, forceload)
    desc = describe(object)
    module = inspect.getmodule(object)
    if name:
        if "." in name:
            desc += " in " + name[: name.rfind(".")]
        if module:
            if module is not object:
                desc += " in module " + module.__name__
    if not (
        inspect.ismodule(object)
        or inspect.isclass(object)
        or inspect.isroutine(object)
        or inspect.isgetsetdescriptor(object)
        or inspect.ismemberdescriptor(object)
        or isinstance(object, property)
    ):
        object = type(object)
        desc += " object"
    return title % desc + "\n\n" + renderer.document(object, name)


def doc(thing, title="Python Library Documentation: %s", forceload=0, output=None):
    """Display text documentation, given an object or a path to an object."""
    try:
        if output is None:
            pager(render_doc(thing, title, forceload))
        else:
            output.write(render_doc(thing, title, forceload, plaintext))
    except (ImportError, ErrorDuringImport) as value:
        print(value)


def writedoc(thing, forceload=0):
    """Write HTML documentation to a file in the current directory."""
    try:
        object, name = resolve(thing, forceload)
        page = html.page(describe(object), html.document(object, name))
        with open(name + ".html", "w", encoding="utf-8") as (file):
            file.write(page)
        print("wrote", name + ".html")
    except (ImportError, ErrorDuringImport) as value:
        print(value)


def writedocs(dir, pkgpath="", done=None):
    """Write out HTML documentation for all modules in a directory tree."""
    if done is None:
        done = {}
    for importer, modname, ispkg in pkgutil.walk_packages([dir], pkgpath):
        writedoc(modname)


class Helper:
    keywords = {
        "False": "",
        "None": "",
        "True": "",
        "and": "BOOLEAN",
        "as": "with",
        "assert": ("assert", ""),
        "break": ("break", "while for"),
        "class": ("class", "CLASSES SPECIALMETHODS"),
        "continue": ("continue", "while for"),
        "def": ("function", ""),
        "del": ("del", "BASICMETHODS"),
        "elif": "if",
        "else": ("else", "while for"),
        "except": "try",
        "finally": "try",
        "for": ("for", "break continue while"),
        "from": "import",
        "global": ("global", "nonlocal NAMESPACES"),
        "if": ("if", "TRUTHVALUE"),
        "import": ("import", "MODULES"),
        "in": ("in", "SEQUENCEMETHODS"),
        "is": "COMPARISON",
        "lambda": ("lambda", "FUNCTIONS"),
        "nonlocal": ("nonlocal", "global NAMESPACES"),
        "not": "BOOLEAN",
        "or": "BOOLEAN",
        "pass": ("pass", ""),
        "raise": ("raise", "EXCEPTIONS"),
        "return": ("return", "FUNCTIONS"),
        "try": ("try", "EXCEPTIONS"),
        "while": ("while", "break continue if TRUTHVALUE"),
        "with": ("with", "CONTEXTMANAGERS EXCEPTIONS yield"),
        "yield": ("yield", ""),
    }
    _symbols_inverse = {
        "STRINGS": ("'", "'''", "r'", "b'", '"""', '"', 'r"', 'b"'),
        "OPERATORS": (
            "+",
            "-",
            "*",
            "**",
            "/",
            "//",
            "%",
            "<<",
            ">>",
            "&",
            "|",
            "^",
            "~",
            "<",
            ">",
            "<=",
            ">=",
            "==",
            "!=",
            "<>",
        ),
        "COMPARISON": ("<", ">", "<=", ">=", "==", "!=", "<>"),
        "UNARY": ("-", "~"),
        "AUGMENTEDASSIGNMENT": (
            "+=",
            "-=",
            "*=",
            "/=",
            "%=",
            "&=",
            "|=",
            "^=",
            "<<=",
            ">>=",
            "**=",
            "//=",
        ),
        "BITWISE": ("<<", ">>", "&", "|", "^", "~"),
        "COMPLEX": ("j", "J"),
    }
    symbols = {
        "%": "OPERATORS FORMATTING",
        "**": "POWER",
        ",": "TUPLES LISTS FUNCTIONS",
        ".": "ATTRIBUTES FLOAT MODULES OBJECTS",
        "...": "ELLIPSIS",
        ":": "SLICINGS DICTIONARYLITERALS",
        "@": "def class",
        "\\": "STRINGS",
        "_": "PRIVATENAMES",
        "__": "PRIVATENAMES SPECIALMETHODS",
        "`": "BACKQUOTES",
        "(": "TUPLES FUNCTIONS CALLS",
        ")": "TUPLES FUNCTIONS CALLS",
        "[": "LISTS SUBSCRIPTS SLICINGS",
        "]": "LISTS SUBSCRIPTS SLICINGS",
    }
    for topic, symbols_ in _symbols_inverse.items():
        for symbol in symbols_:
            topics = symbols.get(symbol, topic)
            if topic not in topics:
                topics = topics + " " + topic
            symbols[symbol] = topics

    topics = {
        "TYPES": (
            "types",
            "STRINGS UNICODE NUMBERS SEQUENCES MAPPINGS FUNCTIONS CLASSES MODULES FILES inspect",
        ),
        "STRINGS": ("strings", "str UNICODE SEQUENCES STRINGMETHODS FORMATTING TYPES"),
        "STRINGMETHODS": ("string-methods", "STRINGS FORMATTING"),
        "FORMATTING": ("formatstrings", "OPERATORS"),
        "UNICODE": (
            "strings",
            "encodings unicode SEQUENCES STRINGMETHODS FORMATTING TYPES",
        ),
        "NUMBERS": ("numbers", "INTEGER FLOAT COMPLEX TYPES"),
        "INTEGER": ("integers", "int range"),
        "FLOAT": ("floating", "float math"),
        "COMPLEX": ("imaginary", "complex cmath"),
        "SEQUENCES": ("typesseq", "STRINGMETHODS FORMATTING range LISTS"),
        "MAPPINGS": "DICTIONARIES",
        "FUNCTIONS": ("typesfunctions", "def TYPES"),
        "METHODS": ("typesmethods", "class def CLASSES TYPES"),
        "CODEOBJECTS": ("bltin-code-objects", "compile FUNCTIONS TYPES"),
        "TYPEOBJECTS": ("bltin-type-objects", "types TYPES"),
        "FRAMEOBJECTS": "TYPES",
        "TRACEBACKS": "TYPES",
        "NONE": ("bltin-null-object", ""),
        "ELLIPSIS": ("bltin-ellipsis-object", "SLICINGS"),
        "SPECIALATTRIBUTES": ("specialattrs", ""),
        "CLASSES": ("types", "class SPECIALMETHODS PRIVATENAMES"),
        "MODULES": ("typesmodules", "import"),
        "PACKAGES": "import",
        "EXPRESSIONS": (
            "operator-summary",
            "lambda or and not in is BOOLEAN COMPARISON BITWISE SHIFTING BINARY FORMATTING POWER UNARY ATTRIBUTES SUBSCRIPTS SLICINGS CALLS TUPLES LISTS DICTIONARIES",
        ),
        "OPERATORS": "EXPRESSIONS",
        "PRECEDENCE": "EXPRESSIONS",
        "OBJECTS": ("objects", "TYPES"),
        "SPECIALMETHODS": (
            "specialnames",
            "BASICMETHODS ATTRIBUTEMETHODS CALLABLEMETHODS SEQUENCEMETHODS MAPPINGMETHODS NUMBERMETHODS CLASSES",
        ),
        "BASICMETHODS": ("customization", "hash repr str SPECIALMETHODS"),
        "ATTRIBUTEMETHODS": ("attribute-access", "ATTRIBUTES SPECIALMETHODS"),
        "CALLABLEMETHODS": ("callable-types", "CALLS SPECIALMETHODS"),
        "SEQUENCEMETHODS": (
            "sequence-types",
            "SEQUENCES SEQUENCEMETHODS SPECIALMETHODS",
        ),
        "MAPPINGMETHODS": ("sequence-types", "MAPPINGS SPECIALMETHODS"),
        "NUMBERMETHODS": (
            "numeric-types",
            "NUMBERS AUGMENTEDASSIGNMENT SPECIALMETHODS",
        ),
        "EXECUTION": ("execmodel", "NAMESPACES DYNAMICFEATURES EXCEPTIONS"),
        "NAMESPACES": ("naming", "global nonlocal ASSIGNMENT DELETION DYNAMICFEATURES"),
        "DYNAMICFEATURES": ("dynamic-features", ""),
        "SCOPING": "NAMESPACES",
        "FRAMES": "NAMESPACES",
        "EXCEPTIONS": ("exceptions", "try except finally raise"),
        "CONVERSIONS": ("conversions", ""),
        "IDENTIFIERS": ("identifiers", "keywords SPECIALIDENTIFIERS"),
        "SPECIALIDENTIFIERS": ("id-classes", ""),
        "PRIVATENAMES": ("atom-identifiers", ""),
        "LITERALS": (
            "atom-literals",
            "STRINGS NUMBERS TUPLELITERALS LISTLITERALS DICTIONARYLITERALS",
        ),
        "TUPLES": "SEQUENCES",
        "TUPLELITERALS": ("exprlists", "TUPLES LITERALS"),
        "LISTS": ("typesseq-mutable", "LISTLITERALS"),
        "LISTLITERALS": ("lists", "LISTS LITERALS"),
        "DICTIONARIES": ("typesmapping", "DICTIONARYLITERALS"),
        "DICTIONARYLITERALS": ("dict", "DICTIONARIES LITERALS"),
        "ATTRIBUTES": (
            "attribute-references",
            "getattr hasattr setattr ATTRIBUTEMETHODS",
        ),
        "SUBSCRIPTS": ("subscriptions", "SEQUENCEMETHODS"),
        "SLICINGS": ("slicings", "SEQUENCEMETHODS"),
        "CALLS": ("calls", "EXPRESSIONS"),
        "POWER": ("power", "EXPRESSIONS"),
        "UNARY": ("unary", "EXPRESSIONS"),
        "BINARY": ("binary", "EXPRESSIONS"),
        "SHIFTING": ("shifting", "EXPRESSIONS"),
        "BITWISE": ("bitwise", "EXPRESSIONS"),
        "COMPARISON": ("comparisons", "EXPRESSIONS BASICMETHODS"),
        "BOOLEAN": ("booleans", "EXPRESSIONS TRUTHVALUE"),
        "ASSERTION": "assert",
        "ASSIGNMENT": ("assignment", "AUGMENTEDASSIGNMENT"),
        "AUGMENTEDASSIGNMENT": ("augassign", "NUMBERMETHODS"),
        "DELETION": "del",
        "RETURNING": "return",
        "IMPORTING": "import",
        "CONDITIONAL": "if",
        "LOOPING": ("compound", "for while break continue"),
        "TRUTHVALUE": ("truth", "if while and or not BASICMETHODS"),
        "DEBUGGING": ("debugger", "pdb"),
        "CONTEXTMANAGERS": ("context-managers", "with"),
    }

    def __init__(self, input=None, output=None):
        self._input = input
        self._output = output

    input = property(lambda self: self._input or sys.stdin)
    output = property(lambda self: self._output or sys.stdout)

    def __repr__(self):
        if inspect.stack()[1][3] == "?":
            self()
            return ""
        else:
            return "<%s.%s instance>" % (
                self.__class__.__module__,
                self.__class__.__qualname__,
            )

    _GoInteractive = object()

    def __call__(self, request=_GoInteractive):
        if request is not self._GoInteractive:
            self.help(request)
        else:
            self.intro()
            self.interact()
            self.output.write(
                '\nYou are now leaving help and returning to the Python interpreter.\nIf you want to ask for help on a particular object directly from the\ninterpreter, you can type "help(object)".  Executing "help(\'string\')"\nhas the same effect as typing a particular string at the help> prompt.\n'
            )

    def interact(self):
        self.output.write("\n")
        while True:
            try:
                request = self.getline("help> ")
                if not request:
                    break
            except (KeyboardInterrupt, EOFError):
                break

            request = replace(request, '"', "", "'", "").strip()
            if request.lower() in ("q", "quit"):
                break
            if request == "help":
                self.intro()
            else:
                self.help(request)

    def getline(self, prompt):
        """Read one line, using input() when appropriate."""
        if self.input is sys.stdin:
            return input(prompt)
        else:
            self.output.write(prompt)
            self.output.flush()
            return self.input.readline()

    def help(self, request):
        if type(request) is type(""):
            request = request.strip()
            if request == "keywords":
                self.listkeywords()
            else:
                if request == "symbols":
                    self.listsymbols()
                else:
                    if request == "topics":
                        self.listtopics()
                    else:
                        if request == "modules":
                            self.listmodules()
                        else:
                            if request[:8] == "modules ":
                                self.listmodules(request.split()[1])
                            else:
                                if request in self.symbols:
                                    self.showsymbol(request)
                                else:
                                    if request in ("True", "False", "None"):
                                        doc(eval(request), "Help on %s:")
                                    else:
                                        if request in self.keywords:
                                            self.showtopic(request)
                                        else:
                                            if request in self.topics:
                                                self.showtopic(request)
                                            else:
                                                if request:
                                                    doc(
                                                        request,
                                                        "Help on %s:",
                                                        output=self._output,
                                                    )
                                                else:
                                                    doc(
                                                        str,
                                                        "Help on %s:",
                                                        output=self._output,
                                                    )
        else:
            if isinstance(request, Helper):
                self()
            else:
                doc(request, "Help on %s:", output=self._output)
            self.output.write("\n")

    def intro(self):
        self.output.write(
            (
                '\nWelcome to Python {0}\'s help utility!\n\nIf this is your first time using Python, you should definitely check out\nthe tutorial on the Internet at http://docs.python.org/{0}/tutorial/.\n\nEnter the name of any module, keyword, or topic to get help on writing\nPython programs and using Python modules.  To quit this help utility and\nreturn to the interpreter, just type "quit".\n\nTo get a list of available modules, keywords, symbols, or topics, type\n"modules", "keywords", "symbols", or "topics".  Each module also comes\nwith a one-line summary of what it does; to list the modules whose name\nor summary contain a given string such as "spam", type "modules spam".\n'
            ).format("%d.%d" % sys.version_info[:2])
        )

    def list(self, items, columns=4, width=80):
        items = list(sorted(items))
        colw = width // columns
        rows = (len(items) + columns - 1) // columns
        for row in range(rows):
            for col in range(columns):
                i = col * rows + row
                if i < len(items):
                    self.output.write(items[i])
                    if col < columns - 1:
                        self.output.write(" " + " " * (colw - 1 - len(items[i])))

            self.output.write("\n")

    def listkeywords(self):
        self.output.write(
            "\nHere is a list of the Python keywords.  Enter any keyword to get more help.\n\n"
        )
        self.list(self.keywords.keys())

    def listsymbols(self):
        self.output.write(
            "\nHere is a list of the punctuation symbols which Python assigns special meaning\nto. Enter any symbol to get more help.\n\n"
        )
        self.list(self.symbols.keys())

    def listtopics(self):
        self.output.write(
            "\nHere is a list of available topics.  Enter any topic name to get more help.\n\n"
        )
        self.list(self.topics.keys())

    def showtopic(self, topic, more_xrefs=""):
        try:
            import pydoc_data.topics
        except ImportError:
            self.output.write(
                '\nSorry, topic and keyword documentation is not available because the\nmodule "pydoc_data.topics" could not be found.\n'
            )
            return
        else:
            target = self.topics.get(topic, self.keywords.get(topic))
            if not target:
                self.output.write("no documentation found for %s\n" % repr(topic))
                return
            if type(target) is type(""):
                return self.showtopic(target, more_xrefs)
            label, xrefs = target
            try:
                doc = pydoc_data.topics.topics[label]
            except KeyError:
                self.output.write("no documentation found for %s\n" % repr(topic))
                return
            else:
                pager(doc.strip() + "\n")
                xrefs = more_xrefs and (xrefs or "") + " " + more_xrefs

            if xrefs:
                import textwrap

                text = "Related help topics: " + (", ").join(xrefs.split()) + "\n"
                wrapped_text = textwrap.wrap(text, 72)
                self.output.write("\n%s\n" % ("").join(wrapped_text))

    def _gettopic(self, topic, more_xrefs=""):
        """Return unbuffered tuple of (topic, xrefs).
        
        If an error occurs here, the exception is caught and displayed by
        the url handler.
        
        This function duplicates the showtopic method but returns its
        result directly so it can be formatted for display in an html page.
        """
        try:
            import pydoc_data.topics
        except ImportError:
            return (
                '\nSorry, topic and keyword documentation is not available because the\nmodule "pydoc_data.topics" could not be found.\n',
                "",
            )
        else:
            target = self.topics.get(topic, self.keywords.get(topic))
            if not target:
                pass
            raise ValueError("could not find topic")

        if isinstance(target, str):
            return self._gettopic(target, more_xrefs)
        else:
            label, xrefs = target
            doc = pydoc_data.topics.topics[label]
            if more_xrefs:
                xrefs = (xrefs or "") + " " + more_xrefs
            return (doc, xrefs)

    def showsymbol(self, symbol):
        target = self.symbols[symbol]
        topic, _, xrefs = target.partition(" ")
        self.showtopic(topic, xrefs)

    def listmodules(self, key=""):
        if key:
            self.output.write(
                (
                    "\nHere is a list of modules whose name or summary contains '{}'.\nIf there are any, enter a module name to get more help.\n\n"
                ).format(key)
            )
            apropos(key)
        else:
            self.output.write(
                "\nPlease wait a moment while I gather a list of all available modules...\n\n"
            )
            modules = {}

            def callback(path, modname, desc, modules=modules):
                if modname:
                    if modname[-9:] == ".__init__":
                        modname = modname[:-9] + " (package)"
                if modname.find(".") < 0:
                    modules[modname] = 1

            def onerror(modname):
                callback(None, modname, None)

            ModuleScanner().run(callback, onerror=onerror)
            self.list(modules.keys())
            self.output.write(
                '\nEnter any module name to get more help.  Or, type "modules spam" to search\nfor modules whose name or summary contain the string "spam".\n'
            )


help = Helper()


class ModuleScanner:
    """An interruptible scanner that searches module synopses."""

    def run(self, callback, key=None, completer=None, onerror=None):
        if key:
            key = key.lower()
        self.quit = False
        seen = {}
        for modname in sys.builtin_module_names:
            if modname != "__main__":
                seen[modname] = 1
                if key is None:
                    callback(None, modname, "")
            else:
                name = __import__(modname).__doc__ or ""
                desc = name.split("\n")[0]
                name = modname + " - " + desc
                if name.lower().find(key) >= 0:
                    callback(None, modname, desc)

        for importer, modname, ispkg in pkgutil.walk_packages(onerror=onerror):
            if self.quit:
                break
            if key is None:
                callback(None, modname, "")
            else:
                try:
                    spec = pkgutil._get_spec(importer, modname)
                except SyntaxError:
                    continue

                loader = spec.loader
                if hasattr(loader, "get_source"):
                    try:
                        source = loader.get_source(modname)
                    except Exception:
                        if onerror:
                            onerror(modname)
                        continue

                    desc = source_synopsis(io.StringIO(source)) or ""
                    if hasattr(loader, "get_filename"):
                        path = loader.get_filename(modname)
                    else:
                        path = None
                else:
                    try:
                        module = importlib._bootstrap._load(spec)
                    except ImportError:
                        if onerror:
                            onerror(modname)
                        continue

                    desc = module.__doc__.splitlines()[0] if module.__doc__ else ""
                    path = getattr(module, "__file__", None)
                name = modname + " - " + desc
                if name.lower().find(key) >= 0:
                    callback(path, modname, desc)

        if completer:
            completer()


def apropos(key):
    """Print all the one-line module summaries that contain a substring."""

    def callback(path, modname, desc):
        if modname[-9:] == ".__init__":
            modname = modname[:-9] + " (package)"
        print(modname, desc and "- " + desc)

    def onerror(modname):
        pass

    with warnings.catch_warnings():
        warnings.filterwarnings("ignore")
        ModuleScanner().run(callback, key, onerror=onerror)


def _start_server(urlhandler, port):
    """Start an HTTP server thread on a specific port.
    
     Start an HTML/text server thread, so HTML or text documents can be
     browsed dynamically and interactively with a Web browser.  Example use:
    
         >>> import time
         >>> import pydoc
    
         Define a URL handler.  To determine what the client is asking
         for, check the URL and content_type.
    
         Then get or generate some text or HTML code and return it.
    
         >>> def my_url_handler(url, content_type):
         ...     text = 'the URL sent was: (%s, %s)' % (url, content_type)
         ...     return text
    
         Start server thread on port 0.
         If you use port 0, the server will pick a random port number.
         You can then use serverthread.port to get the port number.
    
         >>> port = 0
         >>> serverthread = pydoc._start_server(my_url_handler, port)
    
         Check that the server is really started.  If it is, open browser
         and get first page.  Use serverthread.url as the starting page.
    
         >>> if serverthread.serving:
         ...    import webbrowser
    
         The next two lines are commented out so a browser doesn't open if
         doctest is run on this module.
    
         #...    webbrowser.open(serverthread.url)
         #True
    
         Let the server do its thing. We just need to monitor its status.
         Use time.sleep so the loop doesn't hog the CPU.
    
         >>> starttime = time.time()
         >>> timeout = 1                    #seconds
    
         This is a short timeout for testing purposes.
    
         >>> while serverthread.serving:
         ...     time.sleep(.01)
         ...     if serverthread.serving and time.time() - starttime > timeout:
         ...          serverthread.stop()
         ...          break
    
         Print any errors that may have occurred.
    
         >>> print(serverthread.error)
         None
    """
    import http.server, email.message, select, threading

    class DocHandler(http.server.BaseHTTPRequestHandler):
        def do_GET(self):
            """Process a request from an HTML browser.
            
            The URL received is in self.path.
            Get an HTML page from self.urlhandler and send it.
            """
            if self.path.endswith(".css"):
                content_type = "text/css"
            else:
                content_type = "text/html"
            self.send_response(200)
            self.send_header("Content-Type", "%s; charset=UTF-8" % content_type)
            self.end_headers()
            self.wfile.write(self.urlhandler(self.path, content_type).encode("utf-8"))

        def log_message(self, *args):
            pass

    class DocServer(http.server.HTTPServer):
        def __init__(self, port, callback):
            self.host = "localhost"
            self.address = (self.host, port)
            self.callback = callback
            self.base.__init__(self, self.address, self.handler)
            self.quit = False

        def serve_until_quit(self):
            while not self.quit:
                rd, wr, ex = select.select([self.socket.fileno()], [], [], 1)
                if rd:
                    self.handle_request()

            self.server_close()

        def server_activate(self):
            self.base.server_activate(self)
            if self.callback:
                self.callback(self)

    class ServerThread(threading.Thread):
        def __init__(self, urlhandler, port):
            self.urlhandler = urlhandler
            self.port = int(port)
            threading.Thread.__init__(self)
            self.serving = False
            self.error = None

        def run(self):
            """Start the server."""
            try:
                DocServer.base = http.server.HTTPServer
                DocServer.handler = DocHandler
                DocHandler.MessageClass = email.message.Message
                DocHandler.urlhandler = staticmethod(self.urlhandler)
                docsvr = DocServer(self.port, self.ready)
                self.docserver = docsvr
                docsvr.serve_until_quit()
            except Exception as e:
                self.error = e

        def ready(self, server):
            self.serving = True
            self.host = server.host
            self.port = server.server_port
            self.url = "http://%s:%d/" % (self.host, self.port)

        def stop(self):
            """Stop the server and this thread nicely"""
            self.docserver.quit = True
            self.serving = False
            self.url = None

    thread = ServerThread(urlhandler, port)
    thread.start()
    while not thread.error:
        if not thread.serving:
            time.sleep(0.01)

    return thread


def _url_handler(url, content_type="text/html"):
    """The pydoc url handler for use with the pydoc server.
    
    If the content_type is 'text/css', the _pydoc.css style
    sheet is read and returned if it exits.
    
    If the content_type is 'text/html', then the result of
    get_html_page(url) is returned.
    """

    class _HTMLDoc(HTMLDoc):
        def page(self, title, contents):
            """Format an HTML page."""
            css_path = "pydoc_data/_pydoc.css"
            css_link = '<link rel="stylesheet" type="text/css" href="%s">' % css_path
            return (
                '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">\n<html><head><title>Pydoc: %s</title>\n<meta http-equiv="Content-Type" content="text/html; charset=utf-8">\n%s</head><body bgcolor="#f0f0f8">%s<div style="clear:both;padding-top:.5em;">%s</div>\n</body></html>'
                % (title, css_link, html_navbar(), contents)
            )

        def filelink(self, url, path):
            return '<a href="getfile?key=%s">%s</a>' % (url, path)

    html = _HTMLDoc()

    def html_navbar():
        version = html.escape(
            "%s [%s, %s]"
            % (
                platform.python_version(),
                platform.python_build()[0],
                platform.python_compiler(),
            )
        )
        return (
            '\n            <div style=\'float:left\'>\n                Python %s<br>%s\n            </div>\n            <div style=\'float:right\'>\n                <div style=\'text-align:center\'>\n                  <a href="index.html">Module Index</a>\n                  : <a href="topics.html">Topics</a>\n                  : <a href="keywords.html">Keywords</a>\n                </div>\n                <div>\n                    <form action="get" style=\'display:inline;\'>\n                      <input type=text name=key size=15>\n                      <input type=submit value="Get">\n                    </form>&nbsp;\n                    <form action="search" style=\'display:inline;\'>\n                      <input type=text name=key size=15>\n                      <input type=submit value="Search">\n                    </form>\n                </div>\n            </div>\n            '
            % (version, html.escape(platform.platform(terse=True)))
        )

    def html_index():
        """Module Index page."""

        def bltinlink(name):
            return '<a href="%s.html">%s</a>' % (name, name)

        heading = html.heading(
            "<big><big><strong>Index of Modules</strong></big></big>",
            "#ffffff",
            "#7799ee",
        )
        names = [name for name in sys.builtin_module_names if name != "__main__"]
        contents = html.multicolumn(names, bltinlink)
        contents = [
            heading,
            "<p>" + html.bigsection("Built-in Modules", "#ffffff", "#ee77aa", contents),
        ]
        seen = {}
        for dir in sys.path:
            contents.append(html.index(dir, seen))

        contents.append(
            '<p align=right><font color="#909090" face="helvetica,arial"><strong>pydoc</strong> by Ka-Ping Yee&lt;ping@lfw.org&gt;</font>'
        )
        return ("Index of Modules", ("").join(contents))

    def html_search(key):
        """Search results page."""
        search_result = []

        def callback(path, modname, desc):
            if modname[-9:] == ".__init__":
                modname = modname[:-9] + " (package)"
            search_result.append((modname, desc and "- " + desc))

        with warnings.catch_warnings():
            warnings.filterwarnings("ignore")

            def onerror(modname):
                pass

            ModuleScanner().run(callback, key, onerror=onerror)

        def bltinlink(name):
            return '<a href="%s.html">%s</a>' % (name, name)

        results = []
        heading = html.heading(
            "<big><big><strong>Search Results</strong></big></big>",
            "#ffffff",
            "#7799ee",
        )
        for name, desc in search_result:
            results.append(bltinlink(name) + desc)

        contents = heading + html.bigsection(
            "key = %s" % key, "#ffffff", "#ee77aa", ("<br>").join(results)
        )
        return ("Search Results", contents)

    def html_getfile(path):
        """Get and display a source file listing safely."""
        path = urllib.parse.unquote(path)
        with tokenize.open(path) as (fp):
            lines = html.escape(fp.read())
        body = "<pre>%s</pre>" % lines
        heading = html.heading(
            "<big><big><strong>File Listing</strong></big></big>", "#ffffff", "#7799ee"
        )
        contents = heading + html.bigsection(
            "File: %s" % path, "#ffffff", "#ee77aa", body
        )
        return ("getfile %s" % path, contents)

    def html_topics():
        """Index of topic texts available."""

        def bltinlink(name):
            return '<a href="topic?key=%s">%s</a>' % (name, name)

        heading = html.heading(
            "<big><big><strong>INDEX</strong></big></big>", "#ffffff", "#7799ee"
        )
        names = sorted(Helper.topics.keys())
        contents = html.multicolumn(names, bltinlink)
        contents = heading + html.bigsection("Topics", "#ffffff", "#ee77aa", contents)
        return ("Topics", contents)

    def html_keywords():
        """Index of keywords."""
        heading = html.heading(
            "<big><big><strong>INDEX</strong></big></big>", "#ffffff", "#7799ee"
        )
        names = sorted(Helper.keywords.keys())

        def bltinlink(name):
            return '<a href="topic?key=%s">%s</a>' % (name, name)

        contents = html.multicolumn(names, bltinlink)
        contents = heading + html.bigsection("Keywords", "#ffffff", "#ee77aa", contents)
        return ("Keywords", contents)

    def html_topicpage(topic):
        """Topic or keyword help page."""
        buf = io.StringIO()
        htmlhelp = Helper(buf, buf)
        contents, xrefs = htmlhelp._gettopic(topic)
        if topic in htmlhelp.keywords:
            title = "KEYWORD"
        else:
            title = "TOPIC"
        heading = html.heading(
            "<big><big><strong>%s</strong></big></big>" % title, "#ffffff", "#7799ee"
        )
        contents = "<pre>%s</pre>" % html.markup(contents)
        contents = html.bigsection(topic, "#ffffff", "#ee77aa", contents)
        if xrefs:
            xrefs = sorted(xrefs.split())

            def bltinlink(name):
                return '<a href="topic?key=%s">%s</a>' % (name, name)

            xrefs = html.multicolumn(xrefs, bltinlink)
            xrefs = html.section("Related help topics: ", "#ffffff", "#ee77aa", xrefs)
        return ("%s %s" % (title, topic), ("").join((heading, contents, xrefs)))

    def html_getobj(url):
        obj = locate(url, forceload=1)
        if obj is None:
            if url != "None":
                raise ValueError("could not find object")
        title = describe(obj)
        content = html.document(obj, url)
        return (title, content)

    def html_error(url, exc):
        heading = html.heading(
            "<big><big><strong>Error</strong></big></big>", "#ffffff", "#7799ee"
        )
        contents = ("<br>").join(
            (html.escape(line) for line in format_exception_only(type(exc), exc))
        )
        contents = heading + html.bigsection(url, "#ffffff", "#bb0000", contents)
        return ("Error - %s" % url, contents)

    def get_html_page(url):
        """Generate an HTML page for url."""
        complete_url = url
        if url.endswith(".html"):
            url = url[:-5]
        try:
            if url in ("", "index"):
                title, content = html_index()
            else:
                if url == "topics":
                    title, content = html_topics()
                else:
                    if url == "keywords":
                        title, content = html_keywords()
                    else:
                        if "=" in url:
                            op, _, url = url.partition("=")
                            if op == "search?key":
                                title, content = html_search(url)
                            else:
                                if op == "getfile?key":
                                    title, content = html_getfile(url)
                                else:
                                    if op == "topic?key":
                                        try:
                                            title, content = html_topicpage(url)
                                        except ValueError:
                                            title, content = html_getobj(url)

                                    else:
                                        if op == "get?key":
                                            if url in ("", "index"):
                                                title, content = html_index()
                                            else:
                                                try:
                                                    title, content = html_getobj(url)
                                                except ValueError:
                                                    title, content = html_topicpage(url)

                                        else:
                                            raise ValueError("bad pydoc url")
                        else:
                            title, content = html_getobj(url)
        except Exception as exc:
            title, content = html_error(complete_url, exc)

        return html.page(title, content)

    if url.startswith("/"):
        url = url[1:]
    if content_type == "text/css":
        path_here = os.path.dirname(os.path.realpath(__file__))
        css_path = os.path.join(path_here, url)
        with open(css_path) as (fp):
            return ("").join(fp.readlines())
    else:
        if content_type == "text/html":
            return get_html_page(url)
        raise TypeError("unknown content type %r for url %s" % (content_type, url))


def browse(port=0, *, open_browser=True):
    """Start the enhanced pydoc Web server and open a Web browser.
    
    Use port '0' to start the server on an arbitrary port.
    Set open_browser to False to suppress opening a browser.
    """
    import webbrowser

    serverthread = _start_server(_url_handler, port)
    if serverthread.error:
        print(serverthread.error)
        return
    if serverthread.serving:
        server_help_msg = "Server commands: [b]rowser, [q]uit"
        if open_browser:
            webbrowser.open(serverthread.url)
        try:
            print("Server ready at", serverthread.url)
            print(server_help_msg)
            while serverthread.serving:
                cmd = input("server> ")
                cmd = cmd.lower()
                if cmd == "q":
                    break
                elif cmd == "b":
                    webbrowser.open(serverthread.url)
                else:
                    print(server_help_msg)

        except (KeyboardInterrupt, EOFError):
            print()
        finally:
            if serverthread.serving:
                serverthread.stop()
                print("Server stopped")


def ispath(x):
    return isinstance(x, str) and x.find(os.sep) >= 0


def cli():
    """Command-line interface (looks at sys.argv to decide what to do)."""
    import getopt

    class BadUsage(Exception):
        pass

    if "" not in sys.path:
        scriptdir = os.path.dirname(sys.argv[0])
        if scriptdir in sys.path:
            sys.path.remove(scriptdir)
        sys.path.insert(0, ".")
    try:
        opts, args = getopt.getopt(sys.argv[1:], "bk:p:w")
        writing = False
        start_server = False
        open_browser = False
        port = None
        for opt, val in opts:
            if opt == "-b":
                start_server = True
                open_browser = True
            if opt == "-k":
                apropos(val)
                return
            if opt == "-p":
                start_server = True
                port = val
            if opt == "-w":
                writing = True

        if start_server:
            if port is None:
                port = 0
            browse(port, open_browser=open_browser)
            return
        if not args:
            raise BadUsage
        for arg in args:
            if ispath(arg):
                pass
            if not os.path.exists(arg):
                print("file %r does not exist" % arg)
                break
                try:
                    if ispath(arg):
                        if os.path.isfile(arg):
                            arg = importfile(arg)
                    if writing:
                        if ispath(arg):
                            if os.path.isdir(arg):
                                writedocs(arg)
                            writedoc(arg)
                    else:
                        help.help(arg)
                except ErrorDuringImport as value:
                    print(value)

    except (getopt.error, BadUsage):
        cmd = os.path.splitext(os.path.basename(sys.argv[0]))[0]
        print(
            (
                "pydoc - the Python documentation tool\n\n{cmd} <name> ...\n    Show text documentation on something.  <name> may be the name of a\n    Python keyword, topic, function, module, or package, or a dotted\n    reference to a class or function within a module or module in a\n    package.  If <name> contains a '{sep}', it is used as the path to a\n    Python source file to document. If name is 'keywords', 'topics',\n    or 'modules', a listing of these things is displayed.\n\n{cmd} -k <keyword>\n    Search for a keyword in the synopsis lines of all available modules.\n\n{cmd} -p <port>\n    Start an HTTP server on the given port on the local machine.  Port\n    number 0 can be used to get an arbitrary unused port.\n\n{cmd} -b\n    Start an HTTP server on an arbitrary unused port and open a Web browser\n    to interactively browse documentation.  The -p option can be used with\n    the -b option to explicitly specify the server port.\n\n{cmd} -w <name> ...\n    Write out the HTML documentation for a module to a file in the current\n    directory.  If <name> contains a '{sep}', it is treated as a filename; if\n    it names a directory, documentation is written for all the contents.\n"
            ).format(cmd=cmd, sep=os.sep)
        )


if __name__ == "__main__":
    cli()
